View Full Version : Mount 480mm apo nikkor

ad stevenson
23-Sep-2004, 14:52
Just purchased VERY nice 480mm apo nikkor. I can't figure out how to split the elements to mount in a shutter. I've seen the lens mounted in pics. SK GRIMES, etc. How do you take it apart? My first try at this forum ... looks great! Thanks.

Ernest Purdum
23-Sep-2004, 17:44
I've got a 480mm f9 Apo Nikkor. I looked to see if I could find any set screws or anything elso weird, but didn't find anything. I tried to loosen the front cell but couldn't but I doubt if there is any problem other than big stiff threads. If I were anxious to open it up (which I'm not), I wouldn't hesitate to try a small pair of strap wrenches on it. If, however, you want to have it mounted in a shutter, unless you have the capability of cutting fine metric threads to very close tolerances, you are going to have to look to the S.K. Grimes firm or some other specialist to make the adapters required. Why not let them do the disassembly?

Have you considered the expense of having it mounted in a shutter? It will be considerable. There are alternatives which though less convenient would allow you to use the lens and do not require disassembly.

jonathan smith
24-Sep-2004, 03:11
Just send it in to Grimes and they'll do a beautiful job. They did a 360mm APO Nikkor for me and it's my favorite lens. Total cost was about what a good used lens in shutter would be.

Mark Sawyer
24-Sep-2004, 17:31
An ignorant question, as I'm looking for a long lens for my 8x10, and will likely end up with a barrel lens:

Is there any reason why one shouldn't mount the entire lens in front of the shutter? On the one hand, it will make the lensboard assembly more front-heavy (torquing the front standard); but then, it would also give you a little more bellows draw. Any other considerations?

Dan Fromm
24-Sep-2004, 19:20
Mark, the biggest drawback to front mounting is the risk of vignetting. I hang a variety of lenses in front of a #1 on my 2x3 Graphics. With my setups, vignetting is not a problem.

Here's a simple geometric model (spelled similar triangles) that will let you decide if you can get the coverage you need:

Call the radius of the obstruction behind the lens r1. This is usually the diameter of the hole at the back of the shutter. Call the radius of the circle to be covered r2. Call the distance from the lens' exit pupil to the obstruction d1. Call the distance from the lens' exit pupil to the film plane d2 (usually = f). Then if r1/d1 >= r2/d2 the lens will cover the circle. Now go measure and design and calculate.

I hang a large, heavy -- three pounds plus, about 7" long -- lens entirely in front of my little 2x3 Speed's front standard. To save the front standard and bed rails, I put a little crutch under the lens.



Ernest Purdum
24-Sep-2004, 20:31
Mark, this is done quite often with differing results. You can see examples at www.skgrimes.com. In general, it is apt to work well with lenses that work at a fairly narrow angle, but rarely with wide angle lenses unless the lens is small and the shutter huge. Since your camera is an 8X10, you would probably have a lens large enough to need one of the largest shutters. The common ones used for this purpose are the #4 or 5 Ilex, Wollensak and (less often) the Deckel Compound. The largest is the #5 Compound. One major advantage of this approach is that the required adapter does not require near the precision of those made to place cells front and rear of a shutter. This makes a big difference in cost. Some lenses that are particularly appropriate to mount in this manner are those made for the older horizontal reproduction cameras. These cameras are now little used and their lenses are available at very modest prices. Examples are the Goerz Apo Artar, the Schneider Repro-Claron and the Rodenstock Apo-Ronar. These are "dialyte" type lenses, very tolerant of variations in subject/image ratio, physically rather small for a given focal length and work at rather narrow angles.

24-Sep-2004, 20:43
I've always intended to mount a packard shutter on a lensboard and then mount the lenses themselves to the front of that board. But my 4x5s have smallish boards. My 5x7 is more reasonable and I guess with an 8x10 you've got an even bigger board. The downside is the one speed. But with 8x10 I wonder how much you need a shutter.